Vector force conceptual exercise help.

AI Thread Summary
A train traveling up a 3.73-degree incline at 3.25 m/s loses its last car, which then coasts without friction. To solve for how long it takes for the last car to come to rest, the gravitational force component along the incline is calculated using g*sin(3.73). The vertical speed component is considered while the horizontal component is initially ignored. The discussion emphasizes the need to apply vector quantities and forces to find both the time to rest and the distance traveled before stopping. The approach appears to be on the right track for solving the problem.
jwang023
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Homework Statement



This was a problem I needed help on.
A train is traveling up a 3.73 degree incline at a speed of 3.25 m/s when the last car breaks free and begins to coast without friction.
a). how long does it take for the last car to come to rest momentarily?
b). how far did the last car travel before momentarily coming to rest?

Homework Equations



I'm thinking I use some vector quantities/nature of forces?

The Attempt at a Solution

 
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g*sin(3.73) to find the force of gravity. find the y vector of the speed and ignore the x vector for now.
 
Thanks. Got it
 

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